Analog Devices Inc. LTC2256IUJ-12#PBF

Overview

LTC2256IUJ-12#PBF from Analog Devices (formerly Linear Technology) is a 12-bit, 25Msps ultralow-power analog-to-digital converter optimized for high-dynamic-range signal digitization in demanding RF and instrumentation systems. It features 70.5dB SNR, 84dB SFDR at 70MHz input, 0.17psRMS aperture jitter, single 1.8V supply, and supports CMOS, DDR CMOS, or DDR LVDS digital outputs - enabling direct interface with FPGAs in portable medical imaging and multi-channel data acquisition.

For engineers reviewing the LTC2256IUJ-12#PBF datasheet, LTC2256IUJ-12#PBF pinout, LTC2256IUJ-12#PBF application, or LTC2256IUJ-12#PBF equivalent, this page delivers verified specifications, temperature-grade–specific performance (–40°C to +85°C), output mode configuration details, and real-world design context for undersampling IF signals up to 140MHz with stable DC accuracy (±0.3LSB INL).

Technical Context

The LTC2256IUJ-12#PBF implements a 12-bit pipelined ADC core with 800MHz full-power bandwidth sample-and-hold, supporting undersampling of IF frequencies while maintaining 70.5dB SNR at 25Msps. Its differential ENC+/ENC– clock interface accepts sine wave, PECL, LVDS, TTL, or CMOS inputs, and includes an optional duty cycle stabilizer for robust timing across non-50% clock waveforms.

Digital output flexibility includes full-rate CMOS (12 single-ended outputs), double-data-rate CMOS (6 differential-pair outputs), or double-data-rate LVDS (6 differential pairs with programmable 1.75mA/3.5mA drive). The SPI-configurable serial port enables runtime control of randomizer, nap/shutdown modes, and output formatting - all within a 40-pin 6mm × 6mm QFN package rated for industrial temperature operation.

Key Specifications

Pinout & Package

Package: 40-lead (6mm × 6mm) plastic QFN (UJ), exposed pad soldered to PCB ground for thermal and EMI performance. Industrial temperature grade (–40°C to +85°C).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed ADC applications.

Compared with AD9226ASTZ-RL7, the LTC2256IUJ-12#PBF offers 13× lower power and integrated reference at 25Msps, while LTC2257IUJ-12#PBF provides seamless speed scalability within the same footprint and firmware framework - making both alternatives highly contextual rather than universal replacements.

Availability

LTC2256IUJ-12#PBF is available at Aetrix Electronics and suitable for portable medical imaging, multi-channel data acquisition, and software-defined radio receivers requiring stable component supply with guaranteed long-term industrial temperature support.

Supply support for LTC2256IUJ-12#PBF includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and digital signal processing technologies, serving industrial, automotive, communications, and healthcare markets.

The LTC2256IUJ-12#PBF belongs to the LTC225x family of ultralow-power, high-SFDR pipeline ADCs designed specifically for battery-operated and thermally constrained RF/data acquisition systems requiring precision digitization without external support circuitry.

FAQ

What is the maximum analog input frequency supported by the LTC2256IUJ-12#PBF?

The LTC2256IUJ-12#PBF features an 800MHz full-power bandwidth sample-and-hold stage, enabling reliable undersampling of analog inputs up to 140MHz while maintaining specified SNR and SFDR performance. At 25Msps, this supports Nyquist zones beyond the first, making it suitable for direct IF sampling in SDR and test equipment applications where harmonic rejection and spurious-free operation are critical.

Does the LTC2256IUJ-12#PBF require an external reference voltage?

No - the LTC2256IUJ-12#PBF integrates a precision 1.25V reference with ±25ppm/°C drift and supports internal reference operation via the SENSE pin. When SENSE is tied to VDD, it configures a ±1V input range; grounding SENSE selects ±0.5V. An external 0.625–1.3V reference applied to SENSE sets a proportional ±0.8×VSENSE range, eliminating need for external reference ICs in most designs.

How does the LTC2256IUJ-12#PBF handle clock jitter sensitivity?

The LTC2256IUJ-12#PBF achieves 0.17psRMS aperture jitter - among the lowest in its class - through optimized sample-and-hold architecture and differential ENC+/ENC– clock inputs. This translates to <0.02° phase uncertainty at 200MHz, allowing clean digitization of wideband signals without significant SNR degradation, even when driven by moderately noisy clocks.

Can the LTC2256IUJ-12#PBF interface directly with Xilinx Artix-7 FPGAs?

Yes - the LTC2256IUJ-12#PBF supports DDR LVDS outputs with 100Ω on-chip termination and 247–454mV differential swing, matching Xilinx Artix-7 HP I/O banks. Its CLKOUT+/CLKOUT– strobe pair aligns with ISERDES capture windows, and programmable pipeline latency (5.5 cycles in DDR mode) enables deterministic timing closure without external delay elements.

What power-saving modes are available on the LTC2256IUJ-12#PBF?

The LTC2256IUJ-12#PBF offers three low-power states: Nap mode (9mW), Sleep mode (0.5mW), and configurable shutdown via SDI pin in parallel mode. These modes retain register settings and allow rapid wake-up (<1µs), making them ideal for duty-cycled applications like pulsed ultrasound or intermittent sensor logging where average power must be minimized.